50 ideas
| 2056 | Philosophers are always switching direction to something more interesting [Plato] |
| Full Idea: Philosophers are always ready to change direction, if a topic crops up which is more attractive than the one to hand. | |
| From: Plato (Theaetetus [c.368 BCE], 172d) | |
| A reaction: Which sounds trivial, but it may be what God does. |
| 2086 | Understanding mainly involves knowing the elements, not their combinations [Plato] |
| Full Idea: A perfect grasp of any subject depends far more on knowing elements than on knowing complexes. | |
| From: Plato (Theaetetus [c.368 BCE], 206b) |
| 2083 | Either a syllable is its letters (making parts as knowable as whole) or it isn't (meaning it has no parts) [Plato] |
| Full Idea: Either a syllable is not the same as its letters, in which case it cannot have the letters as parts of itself, or it is the same as its letters, in which case these basic elements are just as knowable as it is. | |
| From: Plato (Theaetetus [c.368 BCE], 205b) |
| 2082 | A rational account is essentially a weaving together of things with names [Plato] |
| Full Idea: Just as primary elements are woven together, so their names may be woven together to produce a spoken account, because an account is essentially a weaving together of names. | |
| From: Plato (Theaetetus [c.368 BCE], 202b) | |
| A reaction: If justification requires 'logos', and logos is a 'weaving together of names', then Plato might be taken as endorsing the coherence account of justification. Or do the two 'weavings' correspond? |
| 12596 | Reasoning aims at increasing explanatory coherence [Harman] |
| Full Idea: In reasoning you try among other things to increase the explanatory coherence of your view. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.2.2) | |
| A reaction: Harman is a champion of inference to the best explanation (abduction), and I agree with him. I think this idea extends to give us a view of justification as coherence, and that extends from inner individual coherence to socially extended coherence. |
| 12599 | Reason conservatively: stick to your beliefs, and prefer reasoning that preserves most of them [Harman] |
| Full Idea: Conservatism is important; you should continue to believe as you do in the absence of any special reason to doubt your view, and in reasoning you should try to minimize change in your initial opinions in attaining other goals of reasoning. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.2.6) | |
| A reaction: One of those principles like Ockham's Razor, which feels right but hard to justify. It seems the wrong principle for someone who can reason well, but has been brainwashed into a large collection of daft beliefs. Japanese soldiers still fighting WWII. |
| 2052 | Eristic discussion is aggressive, but dialectic aims to help one's companions in discussion [Plato] |
| Full Idea: Eristic discussions involve as many tricks and traps as possible, but dialectical discussions involve being serious and correcting the interlocutor's mistakes only when they are his own fault or the result of past conditioning. | |
| From: Plato (Theaetetus [c.368 BCE], 167e) |
| 15854 | A primary element has only a name, and no logos, but complexes have an account, by weaving the names [Plato] |
| Full Idea: A primary element cannot be expressed in an account; it can only be named, for a name is all that it has. But with the things composed of these ...just as the elements are woven together, so the names can woven to become an account. | |
| From: Plato (Theaetetus [c.368 BCE], 202b01-3) | |
| A reaction: This is the beginning of what I see as Aristotle's metaphysics, as derived from his epistemology, that is, ontology is what explains, and what we can give an account [logos] of. Aristotle treats this under 'definitions'. |
| 12595 | We have a theory of logic (implication and inconsistency), but not of inference or reasoning [Harman] |
| Full Idea: There is as yet no substantial theory of inference or reasoning. To be sure, logic is well developed; but logic is not a theory of inference or reasoning. Logic is a theory of implication and inconsistency. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.2.2) | |
| A reaction: One problem is that animals can draw inferences without the use of language, and I presume we do so all the time, so it is hard to see how to formalise such an activity. |
| 12597 | I might accept P and Q as likely, but reject P-and-Q as unlikely [Harman] |
| Full Idea: Principles of implication imply there is not a purely probabilistic rule of acceptance for belief. Otherwise one might accept P and Q, without accepting their conjunction, if the conjuncts have a high probability, but the conjunction doesn't. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.2.2) | |
| A reaction: [Idea from Scott Soames] I am told that my friend A has just won a very big lottery prize, and am then told that my friend B has also won a very big lottery prize. The conjunction seems less believable; I begin to suspect a conspiracy. |
| 10216 | We master arithmetic by knowing all the numbers in our soul [Plato] |
| Full Idea: It must surely be true that a man who has completely mastered arithmetic knows all numbers? Because there are pieces of knowledge covering all numbers in his soul. | |
| From: Plato (Theaetetus [c.368 BCE], 198b) | |
| A reaction: This clearly views numbers as objects. Expectation of knowing them all is a bit startling! They also appear to be innate in us, and hence they appear to be Forms. See Aristotle's comment in Idea 645. |
| 2060 | There seem to be two sorts of change: alteration and motion [Plato] |
| Full Idea: There are two kinds of change, I think: alteration and motion. | |
| From: Plato (Theaetetus [c.368 BCE], 181d) |
| 12598 | Reality is the overlap of true complete theories [Harman] |
| Full Idea: Reality is what is invariant among true complete theories. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.2.4) | |
| A reaction: The sort of slogan that gets coined in the age of Quine. The whole manner of starting from your theories and working out to what we think reality is seems to be putting the cart before the horse. |
| 2084 | If a word has no parts and has a single identity, it turns out to be the same kind of thing as a letter [Plato] |
| Full Idea: If a complex or a syllable has no parts and is a single identity, hasn't it turned out to be the same kind of thing as an element or letter? | |
| From: Plato (Theaetetus [c.368 BCE], 205d) |
| 15844 | A sum is that from which nothing is lacking, which is a whole [Plato] |
| Full Idea: But this sum now - isn't it just when there is nothing lacking that it is a sum? Yes, necessarily. And won't this very same thing - that from which nothing is lacking - be a whole? | |
| From: Plato (Theaetetus [c.368 BCE], 205a) | |
| A reaction: This seems to be right, be rather too vague and potentially circular to be of much use. What is the criterion for deciding that nothing is lacking? |
| 15843 | The whole can't be the parts, because it would be all of the parts, which is the whole [Plato] |
| Full Idea: The whole does not consist of parts; for it did, it would be all the parts and so would be the sum. | |
| From: Plato (Theaetetus [c.368 BCE], 204e) | |
| A reaction: That is, 'the whole is the sum of its parts' is a tautology! The claim that 'the whole is more than the sum of its parts' gets into similar trouble. See Verity Harte on this. |
| 2080 | Things are only knowable if a rational account (logos) is possible [Plato] |
| Full Idea: Things which are susceptible to a rational account are knowable. | |
| From: Plato (Theaetetus [c.368 BCE], 201d) |
| 16126 | Expertise is knowledge of the whole by means of the parts [Plato] |
| Full Idea: A man has passed from mere judgment to expert knowledge of the being of a wagon when he has done so in virtue of having gone over the whole by means of the elements. | |
| From: Plato (Theaetetus [c.368 BCE], 207c) | |
| A reaction: Plato is emphasising that the expert must know the hundred parts of a wagon, and not just the half dozen main components, but here the point is to go over the whole via the parts, and not just list the parts. |
| 2050 | It is impossible to believe something which is held to be false [Plato] |
| Full Idea: It is impossible to believe something which is not the case. | |
| From: Plato (Theaetetus [c.368 BCE], 167a) |
| 2076 | How can a belief exist if its object doesn't exist? [Plato] |
| Full Idea: If the object of a belief is what is not, the object of this belief is nothing; but if there is no object to a belief, then that is not belief at all. | |
| From: Plato (Theaetetus [c.368 BCE], 189a) |
| 2045 | Perception is infallible, suggesting that it is knowledge [Plato] |
| Full Idea: Perception is always of something that is, and it is infallible, which suggests that it is knowledge. | |
| From: Plato (Theaetetus [c.368 BCE], 152c) |
| 2067 | Our senses could have been separate, but they converge on one mind [Plato] |
| Full Idea: It would be peculiar if each of us were like a Trojan horse, with a whole bunch of senses sitting inside us, rather than that all these perceptions converge onto a single identity (mind, or whatever one ought to call it). | |
| From: Plato (Theaetetus [c.368 BCE], 184d) |
| 2068 | With what physical faculty do we perceive pairs of opposed abstract qualities? [Plato] |
| Full Idea: With what physical faculty do we perceive being and not-being, similarity and dissimilarity, identity and difference, oneness and many, odd and even and other maths, ….fineness and goodness? | |
| From: Plato (Theaetetus [c.368 BCE], 185d) |
| 2078 | You might mistake eleven for twelve in your senses, but not in your mind [Plato] |
| Full Idea: Sight or touch might make someone take eleven for twelve, but he could never form this mistaken belief about the contents of his mind. | |
| From: Plato (Theaetetus [c.368 BCE], 195e) |
| 2069 | Thought must grasp being itself before truth becomes possible [Plato] |
| Full Idea: If you can't apprehend being you can't apprehend truth, and so a thing could not be known. Therefore knowledge is not located in immediate experience but in thinking about it, since the latter makes it possible to grasp being and truth. | |
| From: Plato (Theaetetus [c.368 BCE], 186c) |
| 2089 | An inadequate rational account would still not justify knowledge [Plato] |
| Full Idea: If you don't know which letters belong together in the right syllables…it is possible for true belief to be accompanied by a rational account and still not be entitled to the name of knowledge. | |
| From: Plato (Theaetetus [c.368 BCE], 208b) | |
| A reaction: In each case of justification there is a 'clinching' stage, for which there is never going to be a strict rule. It might be foundational, but equally it might be massive coherence, or no alternative. |
| 2085 | Parts and wholes are either equally knowable or equally unknowable [Plato] |
| Full Idea: Either a syllable and its letters are equally knowable and expressible in a rational account, or they are both equally unknowable and inexpressible. | |
| From: Plato (Theaetetus [c.368 BCE], 205e) | |
| A reaction: Presumably you could explain the syllable by the letters, but not vice versa, but he must mean that the explanation is worthless without the letters being explained too. So all explanation is worthless? |
| 2091 | Without distinguishing marks, how do I know what my beliefs are about? [Plato] |
| Full Idea: If I only have beliefs about Theaetetus when I don't know his distinguishing mark, how on earth were my beliefs about you rather than anyone else? | |
| From: Plato (Theaetetus [c.368 BCE], 209b) | |
| A reaction: This is a rather intellectualist approach to mental activity. Presumably Theaetetus has lots of distinguishing marks, but they are not conscious. Must Socrates know everything? |
| 2087 | A rational account might be seeing an image of one's belief, like a reflection in a mirror [Plato] |
| Full Idea: A rational account might be forming an image of one's belief, as in a mirror or a pond. | |
| From: Plato (Theaetetus [c.368 BCE], 206d) | |
| A reaction: Not promising, since the image is not going to be clearer than the original, or contain any new information. Maybe it would be clarified by being 'framed', instead of drifting in muddle. |
| 2090 | A rational account involves giving an image, or analysis, or giving a differentiating mark [Plato] |
| Full Idea: A third sort of rational account (after giving an image, or analysing elements) is being able to mention some mark which differentiates the object in question ('the sun is the brightest heavenly body'). | |
| From: Plato (Theaetetus [c.368 BCE], 208c) | |
| A reaction: This is Plato's clearest statement of what would be involved in adding the necessary logos to your true belief. An image of it, or an analysis, or an individuation. How about a cause? |
| 2081 | Maybe primary elements can be named, but not receive a rational account [Plato] |
| Full Idea: Maybe the primary elements of which things are composed are not susceptible to rational accounts. Each of them taken by itself can only be named, but nothing further can be said about it. | |
| From: Plato (Theaetetus [c.368 BCE], 201e) | |
| A reaction: This still seems to be more or less the central issue in philosophy - which things should be treated as 'primitive', and which other things are analysed and explained using the primitive tools? |
| 2088 | A rational account of a wagon would mean knowledge of its hundred parts [Plato] |
| Full Idea: In the case of a wagon, we may only have correct belief, but someone who is able to explain what it is by going through its hundred parts has got hold of a rational account. | |
| From: Plato (Theaetetus [c.368 BCE], 207b) | |
| A reaction: A wonderful example. In science, you know smoking correlates with cancer, but you only know it when you know the mechanism, the causal structure. This may be a general truth. |
| 2047 | What evidence can be brought to show whether we are dreaming or not? [Plato] |
| Full Idea: What evidence could be brought if we were asked at this very moment whether we are asleep and are dreaming all our thoughts? | |
| From: Plato (Theaetetus [c.368 BCE], 158b) |
| 2053 | If you claim that all beliefs are true, that includes beliefs opposed to your own [Plato] |
| Full Idea: To say that everyone believes what is the case, is to concede the truth of the oppositions' beliefs; in other words, the person has to concede that he himself is wrong. | |
| From: Plato (Theaetetus [c.368 BCE], 171a) |
| 2059 | How can a relativist form opinions about what will happen in the future? [Plato] |
| Full Idea: Does a relativist have any authority to decide about things which will happen in the future? | |
| From: Plato (Theaetetus [c.368 BCE], 178c) | |
| A reaction: Nice question! It seems commonsense that such speculations are possible, but without a concept of truth they are ridiculous. |
| 2054 | Clearly some people are superior to others when it comes to medicine [Plato] |
| Full Idea: In medicine, at least, most people are not self-sufficient at prescribing and effecting cures for themselves, and here some people are superior to others. | |
| From: Plato (Theaetetus [c.368 BCE], 171e) |
| 12602 | There is no natural border between inner and outer [Harman] |
| Full Idea: There is no natural border between inner and outer. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.3.4) | |
| A reaction: Perhaps this is the key idea for the anti-individualist view of mind. Subjectively I would have to accept this idea, but looking objectively at another person it seems self-evident nonsense. |
| 12603 | We can only describe mental attitudes in relation to the external world [Harman] |
| Full Idea: No one has ever described a way of explaining what beliefs, desires, and other mental states are except in terms of actual or possible relations to things in the external world. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.3.4) | |
| A reaction: If I pursue my current favourite idea, that how we explain things is the driving force in what ontology we adopt, then this way of seeing the mind, and taking an externalist anti-individualist view of it seems quite attractive. |
| 12601 | The way things look is a relational matter, not an intrinsic matter [Harman] |
| Full Idea: According to functionalism, the way things look to you is a relational characteristic of your experience, not part of its intrinsic character. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.3.3) | |
| A reaction: No, can't make sense of that. How would being in a relation determine what something is? Similar problems with the structuralist account of mathematics. If the whole family love some one cat or one dog, the only difference is intrinsic to the animal. |
| 12592 | Concepts in thought have content, but not meaning, which requires communication [Harman] |
| Full Idea: Concepts and other aspects of mental representation have content but not (normally) meaning (unless they are also expressions in a language used in communication). | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.1.2) | |
| A reaction: Given his account of meaning as involving some complex 'role', he has to say this, though it seems a dubious distinction, going against the grain of a normal request to ask what some concept 'means'. What is 'democracy'? |
| 12590 | Take meaning to be use in calculation with concepts, rather than in communication [Harman] |
| Full Idea: (Nonsolipsistic) conceptual role semantics is a version of the theory that meaning is use, where the basic use is taken to be in calculation, not in communication, and where concepts are treated as symbols in a 'language of thought'. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.1.1) | |
| A reaction: The idea seems to be to connect the highly social Wittgensteinian view of language with the reductive physicalist account of how brains generate concepts. Interesting, thought I never like meaning-as-use. |
| 12593 | The use theory attaches meanings to words, not to sentences [Harman] |
| Full Idea: A use theory of meaning has to suppose it is words and ways of putting words together that have meaning because of their uses, not sentences. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.1.3) | |
| A reaction: He says that most sentences are unique, so cannot have a standard use. Words do a particular job over and over again. How do you distinguish the quirky use of a word from its standard use? |
| 12588 | Meaning from use of thoughts, constructed from concepts, which have a role relating to reality [Harman] |
| Full Idea: Conceptual role semantics involves meanings of expressions determined by used contents of concepts and thoughts, contents constructed from concepts, concepts determined by functional role, which involves relations to things in the world. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.1) | |
| A reaction: This essay is the locus classicus for conceptual-role semantics. Any attempt to say what something IS by giving an account of its function always feels wrong to me. |
| 12589 | Some regard conceptual role semantics as an entirely internal matter [Harman] |
| Full Idea: I call my conceptual role semantics 'non-solipsistic' to contrast it with that of authors (Field, Fodor, Loar) who think of conceptual role solipsistically as a completely internal matter. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.1) | |
| A reaction: Evidently Harman is influenced by Putnam's Twin Earth, and that meanings ain't in the head, so that the conceptual role has to be extended out into the world to get a good account. I prefer extending into the language community, rather into reality. |
| 12600 | The content of thought is relations, between mental states, things in the world, and contexts [Harman] |
| Full Idea: In (nonsolipsistic) conceptual role semantics the content of thought is not in an 'intrinsic nature', but is rather a matter of how mental states are related to each other, to things in the external world, and to things in a context understood as normal. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.3.3) | |
| A reaction: This is part of Harman's functional view of consciousness, which I find rather dubious. If things only have identity because of some place in a flow diagram, we must ask why that thing has that place in that diagram. |
| 12594 | If one proposition negates the other, which is the negative one? [Harman] |
| Full Idea: A relation of negation might hold between two beliefs without there being anything that determines which belief is the negative one. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.1.4) | |
| A reaction: [He attributes this thought to Brian Loar] This seems to give us a reason why we need a semantics for a logic, and not just a structure of inferences and proofs. |
| 12591 | Mastery of a language requires thinking, and not just communication [Harman] |
| Full Idea: If one cannot think in a language, one has not yet mastered it. A symbol system used only for communication, like Morse code, is not a language. | |
| From: Gilbert Harman ((Nonsolipsistic) Conceptual Role Semantics [1987], 12.1.2) | |
| A reaction: This invites the question of someone who has mastered thinking, but has no idea how to communicate. No doubt we might construct a machine with something like that ability. I think it might support Harman's claim. |
| 5064 | Rights are moral significance, or liberty, or right not to be restrained, or entitlement [Mawson] |
| Full Idea: A 'right' can mean 'x counts morally', or 'x is permitted to do this' (liberty), or 'x can't be stopped from doing this' (negative right), or 'someone should provide this for x'. | |
| From: Tim Mawson (Animal Rights talk [2003]), quoted by PG - lecture notes | |
| A reaction: A useful analysis. It is a useful preliminary to considering whether any of these are natural rights. Personally I am sympathetic to that concept. You cannot deny a person's right to self-defence, even when you are sitting on them. Persons have rights. |
| 2058 | God must be the epitome of goodness, and we can only approach a divine state by being as good as possible [Plato] |
| Full Idea: It is impossible for God to be immoral and not to be the acme of morality; and the only way any of us can approximate to God is to become as moral as possible. | |
| From: Plato (Theaetetus [c.368 BCE], 176c) |
| 2057 | There must always be some force of evil ranged against good [Plato] |
| Full Idea: The elimination of evil is impossible, Theodorus; there must always be some force ranged against good. | |
| From: Plato (Theaetetus [c.368 BCE], 176a) |